The present invention relates to system to transform a horizontal take-off and self-sustained horizontal flight airplane into self-sustained horizontal flight, vertical landing and take-off, hybrid integrated airplane.
More particularly, the invention concerns a system of the above kind that transforms an existing traditional airplane into a vertical take-off and landing and horizontal flight airplane by a conversion operation that is extremely simple and not too expensive.
As it is well known, a main advantage, under a practical point of view, of the vertical take-off and landing aircrafts, also known as VTOL (Vertical Take-Off Landing), is the capability of reaching anyone, everything, everywhere when used for transportation and environment and civil protection services.
These advantages are counterbalanced by the high operating costs of the existing VTOL technology, particularly helicopters, with respect to the other vehicles and transportation systems.
Increased costs are due to the very high amount of power necessary to sustain the helicopter during its horizontal flight, in view of the absence of aerodynamical sustaining thrust of the fixed wings which are provided in traditional aircraft.
On the other side, this drawback is partially reduced in view of the absence of transportation costs and time from the town to the airport, since it is possible to directly land downtown, the heliport requiring a reduced space with respect to the traditional airports, thus saving time, and requiring simpler embarkation procedures.
A main object of the present invention is that of merging the capability of VTOL aircraft with the horizontal flight powered by turbo-propulsors or jet engines (in the following this hybrid feature will be indicated by VTOL-HF-Vertical Take-Off Landing-Horizontal Flight).
It is also known to those skilled in the art that two model of aircraft provided with interchangeable integrated VTOL-HF characteristics have been already developed in the international aerospace industry, namely Harrier and V-22 Osprey.
Harriers are military jet aircrafts made in Great Britain by a British Arerospace and McDonnel Douglas joint-venture.
Instead, V-22 Osprey are military turbo-propulsor aircrafts, providing a tiltable rotor-engine group and are made in the United States by Bell Textron and Boeing. It has already been foreseen the realisation of a civil version.
As far as Harrier are concerned, VROL capability is obtained rotating downward the thrust of its main jet engines during the takeoff/landing steps.
Instead, V-22 Osprey VTOL-HF are based on the direct use of the same main engines and of the relevant thrust mechanisms both in the helicopter mode (VTOL) and as turbo propeller (HF) rotating (tilting) from the above toward the bottom the main engines provided at the ends of the wings.
Thrust mechanisms of the V-22 are designed on the basis of a compromise between big propellers and rotor blades, it being necessary that they work both as turbo propeller (HF) and as helicopter (VTOL).
Both solutions concern aircraft specifically dedicated, particularly designed to be used as VTOL-HF: when they are flying horizontally they use the same main engines sized on the basis of the maximum thrust necessary for vertical take-off and landing, with a consequent impact on the operating costs.
The solution suggested according to the present invention provides that the main engines do not tilt upward and downward, remaining in the standard horizontal position (HF) in any flight phase, using the standard propellers or the jet engines already provided for the horizontal flight; the supplemental capability necessary for the VTOL take-off thrust is obtained by the transfer of the thrust to standard rotor VTOL engines operated by hydraulic pumps/actuators, as well as by little tiltable reaction engines provided in the rear portion and/or fuselage, deactivated (not used) during the horizontal flight. Said little reaction engines can also be comprised of ducted turbofan propellers operated or not by the hydraulic system.
The solution suggested according to the present invention provides that main engines do not tilt upward and downward, remaining in the standard horizontal position (HF) in any flight step, using the standard propellers, or the jet engines already provided for the horizontal flight; the supplementary capability necessary for the VTOL take off thrust is obtained by the transfer of the thrust from the same standard engines to VTOL rotors operated by hydraulic pumps/actuators, as well as small tiltable reactors provided in the rear part and/or under the fuselage, deactivated (not usable) during the horizontal flight. Said small reactors can be also comprised of ducted turbo fan propellers powered or not by the hydraulic system.
An object of the present invention is that of providing a low cost vertical take off and landing and self-sustained horizontal flight integrated system (VTOL-HF).
Another object of the present invention is that of providing a system allowing an easy modification by retrofitting the existing vehicles (both new or used airplane and helicopters) for the transformation into VTOL-HF airplane, introducing little structural modifications.
Still another object of the present invention is that of providing a system allowing to improve the safety during the transition phase in an xe2x80x9cone engine outxe2x80x9d situation.
A further object of the present invention is that of realising a system of the above kind which is highly reliable and having advantages under the aerodynamic and loading aspects.
Still another object of the present invention is that of providing a system that can be used on jet engine aircrafts, helicopters and intermodal vehicles (such as boats and cars).
It is therefore specific object of the present invention a system for the transformation of a traditional self-sustained horizontal take off and landing aircraft into hybrid, integrated, self-sustained vertical take-off and landing and horizontal flight comprising, besides the propulsion system already provided in the aircraft, a hydraulic propulsion system, activating at least a blade rotor, to be used during the vertical take-off and landing and transition phases, said hydraulic system being powered by the engines of the aircraft, and at least an auxiliary engine, provided in a rear position and/or under the aircraft, said at least an auxiliary engine being progressively tiltable and swingable between two limit positions, respectively vertical position and horizontal position, said standard propulsion means of the aircraft being deactivated during the vertical take-off and landing and the transition and activated during the self-sustained horizontal flight, and said at least an auxiliary engine and said at least one auxiliary engine being operating during the vertical take-off and landing and the transition and deactivated during the self-sustained horizontal flight.
More particularly, according to the invention, and in function of the aircraft dimensions, one or more blade rotors are provided, operated by a hydraulic propulsion system powered by the main engines, said rotors being provided on the aircraft fuselage, on the front, central or rear portion, or on the wings, in order to guarantee the vertical take-off and landing of the aircraft.
Preferably, according to the invention, said at least one auxiliary engine is comprised of at least a jet engine, or of at least a rocket, or of at least a hydraulically or not powered, ducted turbofan propeller.
Still according to the invention, at least one or more tiltable auxiliary engines are provided, mainly placed in the rear portion of the aircraft or on the bottom portion of the same, to be used during the vertical take-off and landing and transition phases.
Always according to the invention, vertical rotor or rotors are fixed in their position even when they are deactivated during the horizontal flight, being it possible that they are suitably faired within an aerodynamic structures or within the wings.
Furthermore, according to the invention, said rotors can be folded when not used and can be housed within a housing provided in the aircraft fuselage.
According to the invention, said system can be used also to transform helicopters into VROL-HF integrated aircrafts or for boats to be transformed into VTOL water-air vehicle, or for motor vehicles to be transformed into VTOL ground-air vehicles.